When the life of some stars with a great mass ends, what happens?  A supernova.  What created uranium, gold, iron, and other heavier materials?  Supernovae.  People usually cannot see supernovae from earth with their bare eyes.  In 1054, Chinese astronomers discovered a supernova so shiny that it could even be seen in the day, let alone the night.  The supernova left behind a huge cloud of material known as the Crab Nebula.

  Types of supernova

           Scientists specify two types of supernovae-Type 1 and Type 2.  Type 1 supernovae probably happen in binary stars, or two stars that orbit closely with each other.  A type 1 supernovae happens when one of the two binary stars is a small, dense, white dwarf star.  If the companion star ranges too close to the white dwarf that it’s orbiting, the white dwarf’s gravitational pull would draw matter from the other star.  When the white dwarf had gotten 1.4 times as big as the Sun with the matter,  it would collapse in a supernova.

            Type 2 supernovae occur when a star much more massive than the Sun ends its life.  When the star starts burning out, the core of the star quickly collapses releasing amazing energy as neutrinos (a kind of particle smaller than an atom) and electromagnetic radiation (energy that is electric and magnetic).  The energy makes the star explode in a supernova.  The two types of supernovae also are different in the composition of material they toss.                                                                                                                                          

  Remains of supernova                                                             

Many supernovae shine their brightest for a few days.  Then, after a few weeks, they start fading.  Some fade over months, while others fade over years. Some supernovae leave behind an object.  Some supernovae leave a small, dense, neutron star behind.  A neutron star is composed of neutrons mainly.  A very fast spinning and highly magnetized neutron star is known as a pulsar. Others sometimes leave an object called a black hole. A black hole is something with an amazing gravitational pull.  Others just leave an expanding shell of their outer layers.

Discovering supernovae

To discover supernovae, scientists must use the following:                         

      1.  An 8 inch telescope (if the supernova is too far away to be seen with the naked eye)                                                                      

      2.     A CCD camera to mount on the telescope (This will let you look for even fainter supernovae and take photos of it)                                                         

      3.      a PC with 1 to 2 G-bytes at the least for storing photos from the camera, positioning the telescope, making the photos clearer, and comparing all the photos you take to see how the supernova changes                                                                              

      4.     galaxy charts for locating galaxies in which a supernova might be located                           

          Scientists also know where they can find supernovae more common than other places.  They are most often found in the brighter, larger, and older galaxies rather than faint, smaller, younger galaxies.  Spiral galaxies make more supernovae than egg-shaped galaxies.               

       But how do scientists know that what they found is a supernova?  First, they compare their photos with other photos of supernovae to see what one looks like, and if his is one.  Then, they take photos frequently to check for movement to make sure it’s not an asteroid, variable star, or something else.  Next, they make certain with one or more independent master observations.            

Will the Sun become a supernova?

No way!  Number one, our sun isn’t orbiting with a white dwarf.  Number two, our sun isn’t large enough to become a supernova.  furthermore, it will be another billion years until the Sun runs out of fuel and swells into a red giant star and then goes into a white dwarf form.